Protocols allowing for communication between two electronic devices reside at the application layer (layer 7) of the International Organization for Standardization Open Systems Interconnection (ISO/OSI) reference model. The protocols are designed for a particular network architecture to allow for the transfer of message traffic between the two electronic devices.
Prior Art FIG. 1 is a block diagram illustrating a network 100 comprising a client device and a server device 120. The client 100 requests information from the server 120 through a communication channel 130 that couples the client 110 and the server 120 together. The client 110 and the server 120 can be located on any network, such as a local area network (LAN), a wide area network (WAN), through the Internet, etc. A client/server protocol implemented at the application layer (layer 7) of the ISO/OSI reference model is designed to facilitate the transfer of information between the client 110 and the server 120 once the communication channel 130 is established.
Without the firewall 150, the network 100 allows for direct communication between the client 110 and the server 120 through the communication channel 130. Unfortunately, once the network 100 in which the client device 110 and the server 120 use to communicate with each other is altered, the client/server protocol may fail to allow communication between the two devices, especially if the client/server protocol is not set up to recognize the use of proxy servers.
For example, if a firewall 150 is implemented within the network architecture 100 for security measures, communication may not be possible through the communication channel 130 via the application layer protocol. The firewall 150 secures a private network 160 by providing a gateway for information to pass through between a private network 160 and a public network 170. All message traffic is handled at the network layer (layer 3) of the ISO/OSI reference model, by the firewall 150. The firewall 150 inspects the packet header for incoming and outgoing message traffic against a set of rules set up in security tables. If the rules are not violated, then the message traffic will pass through the firewall 150.
In one implementation, the firewall restricts all message traffic coming into and going out from the private network 160. As illustrated in Prior Art FIG. 1, if the client 110 is located within a private network, and the server 120 is located within a public network 170, then there can be no direct communication between the two due to the implementation of the firewall 150.
The private network 160 can comprise a proxy server 180 with an outside LAN connection to allow for communication between electronic devices that are inside the firewall 150 with electronic devices that are outside of the firewall 150 and in the public network 170. As such, the proxy server 180 provides for an alternative pathway 190 to access devices outside the firewall 150.
However, the use of the proxy server in the prior art for communication between the client device 110 and the server 120 may not fully provide for communication between the client 110 and the server 120, especially when the client/server protocol is unaware of the use of a proxy server. Conventional proxy servers attempt to preserve currently implemented client/server protocols, and as such, changes are made at the network layer (level 3) of the ISO/OSI reference model. As a result, the client/server protocol expects to see only the client 110 and the server 120 referenced within the implementation of the client/server protocol, and will fail whenever a third party device intervenes, and is referenced, such as, a proxy server.
Therefore, prior art methods of implementing a proxy server to facilitate communication between two devices that could not communicate at the application layer through a client/server protocol were unable to facilitate the communication.